1. Field of the Invention
The present invention relates to a video display device such as television receiver having menu screen display function, a video output device such as recorder connected to the video display device, and a video system including the video display device and the video output device, and relates to a menu-screen-display control method applied to the video system.
2. Description of Related Art
Recently, a link function has been completed with spread of a flat television receiver, the link function facilitating and smoothing cooperation of such a television receiver (video display device) with an external device (video output device) such as a recorder. In particular, a new-generation DVD (Digital Versatile Disc) recorder has been widely used in recent years, so that it progressively becomes natural that high-definition broadcast data are recorded while keeping high image quality of the data. The link function is necessary for greatly facilitating handling of such recording and the like.
While names of the link function are different depending on manufacturers, a basic standard of the link function is HDMI-CEC (High Definition Multimedia Interface-Consumer Electronics Control). In the HDMI-CEC standard, a control signal according to the CEC protocol is transmitted via an HDMI cable, so that cooperation between devices is achieved. Thus, a user is freed from troublesome passing of a remote controller from one hand to the other hand, or from complicated button operation, so that the user may enjoy a video image or a sound with simple operation.
The HDMI-CEC standard includes a basic inter-device control function using a common command unified among manufacturers, and a unique inter-device control function using a specific command that may be freely developed by each manufacturer, and several proposals have been made on this type of technique.
For example, Japanese Unexamined Patent Application Publication No. 2008-92208 discloses a technique on menu display of each of a video output device and a video display device. In the technique, when a menu of the video output device is pressed, input selection in the video display device is switched to the video output device, so that a menu screen of the video output device is displayed.
Japanese Unexamined Patent Application Publication No. 2008-78961 discloses a technique where information of a recorded program is transferred from a recording device to a video display device, thereby even if input selection in the video display device is not switched to the recording device, the recorded program may be recognized.
Japanese Unexamined Patent Application Publication No. 2008-54300 discloses a technique considering an external device being not compliant to CEC. Generally, which device is active between devices may be grasped by using CEC. However, when a device being not compliant to CEC exists, since the device may not notify another device of a fact that the device itself is active, a different device, which has previously made such active-device notification, is falsely recognized as an active device in communication. To solve this, in the technique of Japanese Unexamined Patent Application Publication No. 2008-54300, when input selection is switched in the video display device, a fact that the device being not compliant to CEC is active is notified from the video display device to another device.